Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, data, and so on. These systems may be multiple-access systems capable of supporting simultaneous communication of multiple terminals with one or more base stations.
It is desirable that these terminals send and receive large amounts of data within a given bandwidth. It is also desirable that these terminals conserve battery power. Typically, sending and receiving large amounts of data may reduce the battery lifetime of a terminal. One way to increase the battery time of a terminal is to use more efficient amplifiers within the terminal. However, these efficient amplifiers may introduce additional distortion to transmit signals and cause significant spectral re-growth distortion.
One solution is to operate these amplifiers near the non-linear region and use a pre-distortion device at the input of the amplifier to counteract the distortion introduced to transmit signals by the amplifier. However, these pre-distortion devices may need a model of the non-linear characteristics of the amplifier to properly adjust the pre-distortion applied. To maintain a model of the non-linear characteristics of the amplifier, feedback may be needed. Such feedback has typically required a dedicated receiver, which may increase both the cost and the chip real estate of the terminal prohibitively. Thus, there is a need for adaptive pre-distortion without the additional hardware of a dedicated receiver.